Bebac and 29-year-old Mokolo, the zoo's other male western lowland gorilla, were diagnosed in 2008 with heart conditions that required treatment with drugs similar to what humans take for high blood pressure. Their health later was said to improve after the pair were put on high-fiber diets.

The two gorillas came to Cleveland in 1994 from Chicago's Lincoln Park Zoo, where they were both born.

Dozens of people posted remembrances and photos of Bebac on the zoo's Facebook page Saturday.